The heat treatment of a substrate in the manufacturing process of a semiconductor device has, for example, employed a vertical type substrate processing apparatus. In the vertical type substrate processing apparatus, a robot hand is used to transfer a storage vessel in an accommodating chamber which temporarily stores such a storage vessel that accommodates a plurality of substrates.
However, the difficulty of miniaturizing a mechanical part of the robot hand has made it hard to reduce a footprint of the apparatus by saving the space of the accommodating chamber.